The government hopes to provide anti-flu drugs for 80% of the population.
More cases of swine flu have been confirmed in the UK, bringing the total to more than 2,700.
Another 204 patients under observation in England were confirmed as having swine flu on Monday, on top of a further 60 Scottish cases on Sunday.
It brings the number of confirmed cases in the UK to 2,773.
Around 30,000 cases of swine flu have so far been detected in 74 countries, and more than 140 people have died worldwide since March.
The new cases included 89 in the West Midlands, 78 in London and 16 in the south east of England.
The swine flu virus claimed its first victim in the UK last week, after a female patient died in a Scottish hospital.
The victim was a woman aged 38 who gave birth prematurely while being treated at the Royal Alexandra Hospital in Paisley.
The death was the first outside the Americas.